Drive system

Abstract

A driving system includes an engine an engine, a motor generator, a gear mechanism, and a controller. The gear mechanism couples the engine and the motor generator to each other. The gear mechanism includes first and second gears. The first and second gears are configured to be supplied with first driving torque from the engine and second driving torque from the motor generator, respectively. The second gear meshes with the first gear. The controller is configured to perform torque control of the engine to make a rate of variation in the first driving torque at the first gear at a time when the following conditional expression (1) is satisfied smaller than that at a time when the following conditional expression (1) is not satisfied.|T2−T1|<Th1  (1)T1 is the first driving torque, T2 is the second driving torque, and Th1 is a first threshold.

The invention claimed is: 
     
       1. A driving system comprising:
 an engine; 
 a motor generator; 
 a gear mechanism that couples the engine and the motor generator to each other; and 
 a controller, 
 wherein the gear mechanism includes a first gear and a second gear, 
 wherein the first gear is configured to be supplied with a first driving torque from the engine, the first driving torque being a torque of a driving force generated by the engine, 
 wherein the second gear is configured to be supplied with a second driving torque from the motor generator, the second driving torque being a torque of a driving force generated by the motor generator, 
 wherein the second gear is configured to mesh with the first gear, and 
 wherein the controller is configured to perform torque control of the engine to make a rate of variation in the first driving torque at the first gear at a time when the following conditional expression (1) is satisfied smaller than a rate of variation in the first driving torque at the first gear at a time when the following conditional expression (1) is not satisfied,
   | T 2− T 1|< Th 1  (1)
 
 
 where T1 is the first driving torque, T2 is the second driving torque, and Thl is a first threshold. 
 
     
     
       2. The driving system according to  claim 1 , wherein the controller is configured to perform the torque control to make a rate of variation in the second driving torque at the second gear at the time when the conditional expression (1) is satisfied greater than a rate of variation in the second driving torque at the second gear at the time when the conditional expression (1) is not satisfied. 
     
     
       3. The driving system according to  claim 2 , wherein the controller is configured to perform the torque control when the first driving torque rises. 
     
     
       4. The driving system according to  claim 3 , wherein the controller is configured to perform the torque control in a case where output requested torque for the engine is equal to or smaller than a second threshold. 
     
     
       5. The driving system according to  claim 4 , further comprising a fluid configured to lubricate the gear mechanism, wherein
 the controller is configured to perform the torque control in a case where a temperature of the fluid is equal to or higher than a reference temperature. 
 
     
     
       6. The driving system according to  claim 2 , further comprising a fluid configured to lubricate the gear mechanism, wherein
 the controller is configured to perform the torque control in a case where a temperature of the fluid is equal to or higher than a reference temperature. 
 
     
     
       7. The driving system according to  claim 3 , further comprising a fluid configured to lubricate the gear mechanism, wherein
 the controller is configured to perform the torque control in a case where a temperature of the fluid is equal to or higher than a reference temperature. 
 
     
     
       8. The driving system according to  claim 1 , wherein the controller is configured to perform the torque control when the first driving torque rises. 
     
     
       9. The driving system according to  claim 8 , wherein the controller is configured to perform the torque control in a case where output requested torque for the engine is equal to or smaller than a second threshold. 
     
     
       10. The driving system according to  claim 9 , further comprising a fluid configured to lubricate the gear mechanism, wherein
 the controller is configured to perform the torque control in a case where a temperature of the fluid is equal to or higher than a reference temperature. 
 
     
     
       11. The driving system according to  claim 8 , further comprising a fluid configured to lubricate the gear mechanism, wherein
 the controller is configured to perform the torque control in a case where a temperature of the fluid is equal to or higher than a reference temperature. 
 
     
     
       12. The driving system according to  claim 1 , further comprising a fluid configured to lubricate the gear mechanism, wherein
 the controller is configured to perform the torque control in a case where a temperature of the fluid is equal to or higher than a reference temperature.